In general, portable apparatuses may be portable electronic devices that include apparatuses that can provide a communication function capable of calling or exchanging data as they move, such as a cellular phone, a PDA (Personal Digital Assistant), a PCS (Personal Communication Services phone), an IMT (International Mobile Telecommunication)-2000 terminal, a GSM (Global System for Mobile Communication) terminal, and the like, and devices for content playback, such a PMP (Portable Multimedia Player), an MP3 (MPEG audio layer-3) player, and the like.
Recently, in such portable apparatuses, not only the existing mechanical key input unit but also a touch screen for simultaneous input/output functions has been mainly used.
Since the touch screen can serve as a key input unit, provide a relatively large screen, and have a simple and slim design, it has been applied to a portable apparatus in diverse manners.
Alternatively, a graphical user interface that is used in the recent portable apparatus' has evolved into a three-dimensional (3D) user interface using a touch screen, further diversifying the existing form.
Also, a three-dimensional stereophonic display that enables a user to recognize an image displayed on a display screen in three dimensions has been continuously researched.